Machine for reprocessing phonograph record disks



March 195-2 N. T. ALMQUIST ET AL 2,589,185

MACHINE FOR REPROCESSING PHONOGRAPH RECORD DISKS 8 Sheets-Sheet 1 Filed July 15, 1949 I h S m a 9? I I I i m w w E N V u E Q m we mm Nm .m\ M IIN\II 5m Om 93 Mm w ww 4.6

I ///II FITTORWEY March 1952 N. T. ALMQUIST ET AL 2,589,185

MACHINE FOR REPROCESSING PHONOGRAPH RECORD DISKS Filed July 15, 1949 8 Sheets-Sheet 2 INVENTORS N/LS T, FILMQU/ST HNTHONY C.DENHPOLI, JR. BY

HTTORNEY March 11, 1952 N. T. ALMQUIST ET AL 2,589,185

MACHINE FOR REPROCESSING PHONOGRAPH RECORD DISKS 8 Sheets-Sheet 3 Filed July 15, 1949 INVENTORS N/LS TI HLMQU/ST gp/THO/VY C,DENFIPOL HTTORNEY March 1952 N. T. ALMQUIST ETAL 2,589,185

MACHINE FOR REPROCESSING PHONOGRAPH RECORD DISKS Filed July 15, 1949 8 Sheets-Sheet 4 F7 TTORNE 7 March 1.1, 1952 N. T. ALMQUIST ET AL 2,589,185

MACHINE FOR REPROCESSING PHONOGRAPH RECORD DISKS Filed July 15, 1949 8 Sheets-Sheet 5 INVENTORS N/LS 7: HLMQU/ST HN THO/V Y C. DENHPOL I, JR.

HTTORNEY March M, 1952 N. T. ALMQUIST ET AL 2,589,185

MACHINE FOR REPROCESSING PHONOGRAPH RECORD DISKS Filed July 15, 1949 8 Sheets-Sheet 6 L-nn'm IIIIIIIIII'IIIIIIIIIIIIIIIIIIIIII III II IN VEN TORS FIN THONY c. DNHPOL/,JR.

HTTORNEY March 11, 1952 ALMQUIST ET AL 2,589,185

MACHINE FOR REPROCESSING PHONOGRAPH RECORD DISKS Filed July 15. 1949 8 Sheets-Sheet 7 INVENTORS NILS r FILMQU/ST gymmw a. [)/VFIPOLI, JR.

HTTURNEY 11, 1952 N. T. ALMQUIST ETAL 2,589,185

MACHINE FOR REPROCESSING PHONOGRAPH RECORD DI SKS Filed July 15, 1949 8 Sheets-Sheet 8 SlJA-JMOGE- HHLHHH IIVVEIVTORS MN 7'." HLMQU/ST FiNTHO/VY 6*. DE NHPoL/Jm BY HTTQRNEY i atented Mar. 11, 1952 UNITED STATES PATENT OFFICE MACHINE FOR REPROCESSING PHONO- GRAPH RECORD DISKS Nils. T...Almquist,,New Britain, and Anthony C. De: Napoli, Jr.,. Windsor, Conn., assignors. to The: Soundscriber Corporation, New Haven, Cnn.,,--a corporation of Connecticut Application July 15, 1949', Serial NO. 105004 6; Claims- This invention relates. to-machines for reprocessing phonographic record disks, and more particularly to a machine for restoring used phonographic record disks to a substantially new and blank condition in whichtheywill again be suit.- able for receiving new recordings.

The machine herein disclosed will be found particularly useful for carrying out the process disclosed in the Patent; Number 2,539,713, to Donald F; Balmer, issued January 30, 1951,. entitled Reprocessing Phonograph Record Disks, and constitutes an improved form of 'theapparatusv described therein.

The above-mentioned Balmer process is applicable to record disks composed of or having a surface layer of any pl'asticmaterial which is capable of strain relief without melting when heated to a practicable temperature, and in which material recordz grooves have been impressed, indented, or embossed while thematerial is in asolid state andwithout appreciable cutting or breaking of the material. One example. of such a material is a copolymer of vinyl chloride and vinyl acetate, known as Vinylite.

Broadly speaking; the process: includes the step, of heating each disk toa temperature 'whi'ch is below the melting point: and at which strains produced in the material by the recordingoperation will be relieved, whereby therecord grooves will be obliterated; and the stepofspinning the disk aboutits normal axis during and after said heating step, whereby the disk will cool and .set in a fiat condition. Greases or other deformations which mayhave been accidentally imparted to the disks will also be eliminated during the process, providing the material has not actually been broken.

The machine which is the subject of the present application will also be capable: of restoring disks of the above-mentioned type of'material having permanent molded or cut grooves in which a sound track of wave form. has subsequently been impressed. Themachine will not, of course, eliminate the'gro'oves from such disks, but will obliterate the sound track so that the restored disks will have blank grooves which may again be impressed with new sound tracks.

One object of the present invention is to provide an improved machine for efliciently performing the above-mentioned process.

Another object is to provide a machine of the above nature in which a record reprocessing cycle will be automatically completed after being manually initiated.

Another object: is to provide a machine. of the above. nature which may be operated con-veniently, safely, and with a minimum of attention on the part of the, operator.

Another object is to provide a machine of the above nature which is adapted to obliterate soundtracks from one or both sides of record.

disks without producing any substantial deformations therein, whereby no subsequent operations will be necessary in. order to place thedisks in a useable condition- A further object is to provide a machine of theabove nature which will besimple in construction, economical to manufacture, and operate, easy to install and manipulate, compact, ornamental in appearance, and very efficient and durable in use.

With these and other objects in view there; has been illustrated, on the accompanying drawings one form in which the invention may conveniently be embodied in practice.

Inthe drawings,

Fig. 1 is a side view of the improved record disk reprocessing machine, showing in broken lines portions of the interior mechanism thereof.

Fig. 2 is av tron-t View of the same.

:Fig. 3 is a cross-sectional view, taken through the heating chamber, on the line 33 of Fig 1-.

Fig. 4 is a cross-sectional plan view of the same, taken on. the broken line 4 4 of Fig. 1.

Fig. 5 is across-sectional view, taken on. the line 5-5 of Fig. 4., showing the cover-operating mechanism-parts of the machine being omitted in the interest of clarity.

Fig, 6 is a partial cross-sectional view, taken approximately on the line 6-6-of Fig. 4, showing the motor switch in theposition it occupies when the machine cover is closed and the switch contacts are open, and also showing the cycle counter.

Figs. 7 and 8 are partial cross-sectional views similar to Fig. 6, but showing the motor switch in the positions it occupies respectively when the starting button is. pressed to. close the contacts for starting the machine cycle, and when the contacts are aboutto be opened at the end of the. machine cycle.

Fig. 91s a front perspective view of the machine as it would appear with the cover open, and showing a record disk in reprocessing position therein.

Fig. 10 is arear perspective view of the machine as it wouldappear with the cover closed.

Fig. 11 is a diagramof'theelectrical circuits of the machine.

The basic parts of the machine will first be de- 3 scribed with reference to the process, after which a detailed description of the machine will be given.

Referring now to the drawing, in which like reference numerals denote corresponding parts throughout the several views, the numeral I (Figs. 9 and 10) indicates a main body portion which has a rear compartment II containing the necessary operating mechanism, and a relatively shallow open-topped forward compartment or well I2. The body portion In also has a vertically swingable cover I3 which is adapted to close the well I2, and which covers the rear compartment I I at all times.

In order to support a thin record disk D which is to be reprocessed, provision is made of a rotatable horizontal spindle I4 which is inserted in a central aperture of the disk D and which projects forwardly from the rear compartment I I in such a position as to hold the disk D in a vertical plane with its lower portion disposed in the well I2. The upper and central portions of the disk D will be so disposed as to be received within a heating chamber I5 in the forward portion of the cover I3 when said cover is closed. Thus, it will be seen that the disk D is adapted to be completely enclosed in a large chamber formed by the heating chamber I5 and the well I2.

The front of the body portion I0 is provided with a main switch knob l6 for initially energizing the machine, and a starting button I! for initiating a reprocessing cycle of the machine.

When the disk D is in position upon the spindle I4 and the machine is in condition for operation, pressure upon the starting button I! will start a continuous rotation of the spindle I4 so as to spin the disk D rapidly and thus maintain the latter in a fiat condition, and will also cause the cover I3 to close so that the heating chamber I5 will embrace a major portion of the disk D.

After a predetermined time interval, which is sufficient to permit the heating chamber I5 to relieve internal strains in the disk D and thus obliterate the grooves or sound tracks therefrom, the machine will operate automatically to open the cover I3, removing the heating chamber from the disk D, and permitting the latter to cool while the rotation of the spindle I4 is continued. At the end of another time interval, which is sufl'icient to permit the disk D to cool and regain its original self-supportin condition, the rotation of the spindle will be automatically terminated, and the machine cycle will be ended.

Excepting for a brief initial warm-up period, the heating chamber I5 will be maintained at operating temperature during th entire time that the main switch knob I6 is turned on. However, the temperature in the chamber I5 may be adjusted by means of a temperature control knob I8 on the cover I3, as will be further described hereinafter.

Body portion which has an upstanding peripheral flange 20, and which also has a plurality of resilient feet 2| secured to its lower surface. In order to enclose the rear compartment I I, the base plate I9 is provided with a vertical transverse wall 22 at the front of said compartment, and a pair of side walls 23, 24 whcih are set inwardly a short distance from the respective side edges of the base plate I9 and terminate substantially flush with the rear edge of said base plate.

The rear of the compartment II is closed by a removable back plate 25, the upper portion of which is provided with a pair of threaded interior studs 25a having wing nuts 25b, whereby said back plate may be secured to a cross bar 250 attached to the rear ends of the compartment side walls 23, 24 (Figs. 1 and 4), in such a manner as to prevent removal of the back plate 25 from the outside of the machine.

The forward compartment or well I2 is enclosed by means of a U-shaped member 26 having a front wall 21 and side walls 28, 29, embracing the respective front and sides of the base plate I9 (Figs. 4 and 9). The U-shaped member 26 also comprises continuous inwardly-extending upper and lower flanges 30, 3| which respectively abut the side walls 23, 24 of the rear compartment II and engage lower side edge portions of the base plate I9 (Fig. 3).

In order to hold the U-shaped member 26 in place, the upper flange 30 is engaged over the laterally projecting ends of a transverse angle member 32 which is attached to the front surface of the transverse wall 22, the rear ends of the side walls 28, 29 also being provided with inwardlyextending apertured flanges 33 (Fig. 4) which are detachably secured to the ends of the back plate 25 by means of screws 34.

The machine is preferably provided with a pair of side handles 34a, 34a, which are vertically swingable upon hinge pins 341), said hinge pins being mounted upon bases 340 which are attached to the sides of the U-shaped member 26 by means of screws 34d (Figs. 2 and 3) In order to mount the cover I3 swingably upon the body portion Ill, provision is made of a horizontal transverse shaft 35 which is rotatably supported in upper rear portions of the side walls 23, 24 of the rear compartment I I (Figs. 4 and 5) The cover I3 comprises an inner frame 36 which includes the heatin chamber I5 and which is provided with a pair of side arms 31, 38 extending rearwardly from said heating chamber and rigidly secured to opposite ends of the cover shaft 35 outwardly of the side walls 23, 24. It will be seen that the heating chamber I5 is disposed within the front portion of the cover I3, the end walls of said chamber being formed by forward end portions of the side arms 31, 38 (Figs. 3 and 4).

The front and rear walls of the heating chamber I5 are provided by a pair of fiat rectangular heaters 39, 40 of the electrical resistance type, which are integrally joined by means of a horizontal top wall 4 I' (Figs. 1, 3, and 5). The heaters 39, 46 (Figs. 4 and 5) each comprise an inner metal covering 42 and an outer metal covering 43 having a heat insulating sheet 4 5 therebetween, said inner covering 42 and said insulating sheet 44 being continuous across the top of the heating chamber I5 and formin the top wall 4| (Figs. 3, 4, and 5).

The heaters 39, 40 also have flat heating elements 45, 46, respectively, which comprise loops of resistance wire 4?, 48 (Figs. 2 and 3) disposed inwardly of the insulating sheets 44 and separated from the inner metal coverings 42 by means of layers of insulating material 49 (Fig. 5).

It will be seen that the heaters 39, 40 constitute the front transverse portion of the inner frame 36 and are attached to the side arms 31, 38 by means of cars 56 (Figs. 3 and 4) said heaters being so disposed as to occupy vertical positions in equidistant spaced relation to the disk D when the cover I3 is closed.

In order to control the temperature within the heating chamber I5, provision is made of an elongated thermostaticswitch SI, of anysuitabletype (Figs. 1, 3., and 4.) which is mounted. in a vertical position within the heating'chamber I5 andis attached to the side arm 38 by a. clampingdevice 52.

The thermostatic switch 5I is. adapted to be adjusted by means of a manually rotatable shaft 53 (Fig. 3) which extends upwardly through an aperture in the top wall M and which has the temperatureadjusting knob I8 secured thereon.

In. order to facilitateconnection of .the heaters 39, 48 and the thermostatic switch .51 into the electrical circuits of themachine, the top wall M of the heating chamber ISpreferably has a plurality of insulated screw terminals 54 mounted therein.

The inner cover frame 36 further comprises an inclined longitudinal top member 55. which is channel-shaped in cross-section and: is attached at itsfront end to. the top wall 4|. of the heating chamber I5 so as to be disposed approximately midway between the side arms 3], 38. The top member 55 extends rearwardly and is attached at its rear end to the upper end of a channelshaped arm 56 which is mounted upon thetransverse cover shaft 35.

In order to protect and. enclose the inner cover frame 85 and the mechanism within the rear machine compartment I I, the cover I3 includes a shield 5i having a. vertical front wall 58, vertical side walls 59, 68, and a top wall 61, a portion of said top wall being inclined downwardly toward the rear of the machine. In order to support the cover shield 51, the forward sections of the inner frame side arms 31, 38 are provided with upwardly-extending abutment portions 62, 63 (Figs. 1 and 3) which engage the inner surface of the top wall 61 of said shield 51, while rear portions of the side walls 59, fillare attached to the side arms 3.1, 38 a short distance below the cover shaft 35 by means of screws 84, 65. The cover shield 51 is adapted to be retained in place against the abutment portions 62, 63 by means of a latch, which may be in the form of a. key-operated lock 66 having a swingable arm 61 adapted to be engaged through an elongated. aperture 68: in the top frame member 55. The. lock 66 will prevent unauthorized removal of the cover shield 51 and tampering with the machine mechanism. The keys for the lock 6.6 may, of course, be held by the owner of the machine, a designated service man, or any other person.

It will be seen that the cover shield 51 is of ample lateral dimensions to prevent engagement thereof with the body portion IO- when the cover I3 is in its closed position, the closing movement of said cover being limited by engagement of the lower edges of the side arms 31, 38 with the upper flange 38 of the U-shaped member 26.

In order to substantially close the rear compartment I I when the cover I3 is in open position, and at the same time to provide clearance for swinging movement of the heater 48 with the cover I3, the transverse wall 22 is provided with a rearwardly ofiset vertical upward extension 69 having rearwardly-extending end wings 1-8, II attached to the upper edges of the side walls 23, 24, of the rear compartment I I (Fig. 4)

The outer surfaces of the end wings 70, II are previded with fiber spacer blocks I2, I3 which are secured thereto by means of countersunk screws I4, It. The spacer blocks I2, I3 are for the purpose of preventing the alignment of the side arms 8!, 88 during handling and shipment of the machine, and will not normally engage said sid arms during operation,

6. Operating mechanism In order to rotatably support the horizontal spindle I4 and, also to perform other machine functions to be described, provision is made of a gear box I6 which is secured in a central position upon the rear surface of the transverse wall 22 by means of'mounting screws 11. The gear box '16 has an elongated front bearing I8 which projects forwardly through the transverse wall 22' above the well I2, and arearbearing I9 located in the rear compartment I I, said bearing being so disposed as to supportthe spindle I4.in a central horizontal position extending forwardly and rearwardly of the machine.

The record disk D is adapted to be detachably held upon the front end portion of the spindle I4 by a clamping means which comprise a sleeve 88 fixed upon saidv spindle (Figs. 1 and 4) and an apertured knurled knob 81 whichis. removably held upon the spindle by means of an inner spring-pressed ball 82 adapted to engage in a peripheral groove 83 of the spindle. (Fig. 1) It will thus be seen that the. record disk D may readily be placed upon the spindle I4 so as to engage the sleeve 80, the spindle. being inserted in the central aperture of said disk, after which the knob 8i may be, applied to thespindle outwardly of the disk, D. It will be noted that the groove 83 in the spindle I4 isso'disposed that thespringpressed ball 82 will engage an. outer inclined wall, of the groove 83, thus tending. to urge the knob 8,I inwardly so asv to exertamoderate clamping force which will be sufficient to insure rotation of the disk D withthe'spindle I4.

Although the disk clamping knobv 8I will ordinarily remain sufficiently cool during use to permit it to be comfortably handled, provision may be made of a duplicate spare knob. 8 I a which may be substituted for the knob 8| so as to permit the latter to cool in the event that it should become hot during prolonged use. A pair of vertical supporting studs 83a, 83b are secured to the base plate I9 withinthe forward compartment I2 for holding the knobs Ill and Ma in readily available positions when not in use.

The spindle I 4 is, adapted to be driven by means of an electric motor 84. (Fig. 4) which. has a horizontal shaft 85 parallel to the spindle I4 andwhichv isswingably mounted in. the rear compartment I I by means of a. hinged bracket 86. The bracket 86 has a horizontal pivot pin. 81 (Figs. 1 and 4'), and is attached to an upper rear portion of the side wall 24..

The forward end of the motor shaft 85 is provided with a driving pulley 88 which is adapted to drive the spindle I4 by means of a relatively large pulley 89 fixed upon the rear end of said spindle and connected to said pulley 88 by means of a, belt 98, the weight of the motor 84 maintaining a degree of tension in said belt because of the action of the hinged bracket 86.

The speed of. the motor 84 and the relative diameters of the pulleys. 88 and 88 will be so selected as to rotate the spindle I4 at a speed which is sufficient to maintain the record disk D fiat by the action of centrifugal force when said disk is in a soft and limp condition. It has been found in practice that a speed of rotation of approximately 800 revolutions per minute in the spindle I4 will produce satisfactory operation, although it will be understood that the machine may, if desired, be so constructed that the spindle It will be driven at other speeds.

In order to operate the vertically swingable cover I3 and to control the cycle of machine operation, the gear box 16 is provided with a slow speed shaft 9| which is disposed in a transverse position below the spindle I4 and which is operated in a counterclockwise direction thereby, as viewed in Fig. 5, at a speed of approximately 1 revolution in 25 seconds. The slow speed shaft 9| has fixed thereon a cover-lifting cam 92 which is adapted to swing the cover I3 upwardly by means of a linkage comprising a swingable arm 93 pivotally mounted in a bracket 94 on the base plate I9, and a pair of pivoted links 95 connecting the upper end of the arm 93 with an upper portion of the arm 56 on the cover pivot shaft 35 (Figs. 4 and 5). The swingable arm 93 is provided with a roller 96 which serves as a follower for the cover-lifting cam 92 and which will be maintained against the periphery of said cam "by the weight of said cover I3.

It will be seen that the cover lifting cam 92 has a circular edge portion 91 which extends over a major part of the periphery of the cam and will provide a dwell interval of approximately I5 seconds during which the cover I3 will be in its raised or open position. The cover lifting cam 92 also has a flat edge portion 98 which will permit the roller or follower 96 to move forwardly, and thus allow the cover I3 to descend so that the heating chamber I5 will embrace the disk D. It will be noted that the lower edge portion of the heater 40 is provided with an upwardly-extending slot 98a (Figs. 2 and 9) which is adapted to receive the front bearing 18 of the gear box 16, and thus will permit the cover I3 to descend to its full extent.

To provide smooth operation of the cover I3 and also to avoid excessive stresses in its operating mechanism, said cover is partially counterbalanced by means of a coil spring 99, the rear end of which is attached to a stud I on the arm 56 below the cover pivot shaft 35. of the counterbalancing spring 99 is provided with a tapered base IOI which is adjustably threaded upon the rear end of an elongated adjusting screw I02 having a head I03 whereby said screw is held in an aperture in the transverse wall 22.

Thus, it will be seen that the screw head I03 is accessible at the front of the transverse wall 22 so that the spring 99 may be readily adjusted by means of a screwdriver. The spring 99 will, of course, be so adjusted as to relieve the cover lifting cam 92 of a major portion of the weight of the cover I3, while permitting the cover I3 to close promptly by its own weight when the roller 96 rides onto the flat portions 98 of the cover-lifting cam 92.

In order to permit manual initiation and automatic termination of the machine cycle, the machine is provided with a motor switch I04 (Fig. 6) of a type having an operating button I adapted to break a circuit when pressed inwardly and to clos said circuit when released. As shown diagrammatically in Fig. 11, the motor switch I04 comprises a pair of contacts I06, I01 to be further described hereinafter with reference to the electrical circuits of the machine.

The motor switch I04 is mounted for forward and rearward swinging movement upon the base plate I9 by means of a bracket I00 having a transverse pivot pin I 09, and is disposed opposite and rearwardly of an outer end portion of the slow speed shaft 9|. The motor switch I04 is so connected mechanically to the starting button I1 that pressure upon said button will swing said switch rearwardly for closing the contacts The front end I06, I01. This mechanical connection comprises a horizontal shaft IIO upon which the button I1 is integrally secured, said button and said shaft being slidably supported in the front wall 21 of the U-shaped member 26 and in the transverse wall 22, respectively (Fig. 6).

The shaft I I0 (Fig. 6) is connected to the motor switch I04 by means of a link I I I having an angular forward end I I2 which is disposed in an aperture in said shaft and which is adapted to abut the rear surface of the wall 22. The motor switch I04 will normally be held in a vertical position, however, by means of a coil spring II3 which embraces the shaft H0 and is engaged between the outer surface of the transverse wall 22 and a washer I I4 held by a cotter pin in the shaft IIO. Thus, after the starting button l1 has been pressed so as to tilt the motor switch I04, it will return to its outer position because of the action of the spring II3, the outward movement of said shaft IIO being limited by engagement of the angular end II2 of the link III with the wall 22.

Provision is made of a. shut-oil cam I I5 (Fig. 6) which is adapted to depress the operating button I05 when the motor switch I04 is in its vertical position, said cam being secured upon the outer end of the slow speed shaft 9I by means of a set screw H6, and having a projecting cam piece in the form of a headed screw II1 adjustably held by means of a jam-nut H8. The head of the screw H1 is adapted to engage the upper end of a leaf-spring I I9 which is attached at its lower end to the motor switch I04 and which is disposed in engagement with the operating button I05. The leaf spring H9 is so constructed as to lie in an outward position when disengaged from the headed screw II1, as shown in Fig. '7, thus permitting the operating button I05 to occupy an outward position (in which the switch contacts I06, I01 are closed).

It will be understood, however, that the effective force of the coil spring H3 is relatively so strong that when the screw II1 engages the leaf-spring II9, the motor switch I04 will remain in a vertical position and thus permit the action of the screw II1 to depress the operating button I05, as shown in Fig. 6 (and thus open the switch contacts I06, I01).

In order to record the number of cycles performed by the machine, and thus serve as a convenient means for indicating the number of disks reprocessed, provision is made of a suitable counter I20 (Fig. 6) which is secured to the inner surface of the upper wall extension 69 by means of screws I2I, and which is observable through an aperture I22 in said extension. The counter I20 is preferably of the type which is provided with a rearwardly-extending oscillatable operating arm I23, said operating arm being connected to a lateral crank pin I24 on the shut-off cam II5 by means of a link I25. Thus, each machine cycle and attendant revolution of the slow-speed shaft 9I will cause the counter I20 to register an additional unit.

Visual inspection of the record disk D will be permittedwhile the cover I3 is closed by means Of a window I26 which is provided in the central portion of the front wall 21 of the forward compartment I2 (Figs. 2 and 9) In order to illuminate a portion of the disk D when said disk is of translucent or transparent material, and also to serve as a reminder that the machine is turned on, provision is made of a pilot lamp I21 (Figs. 1 and 2), which is held in a socket I28 in the rear compartment II and which projects forwardly through an aperture in the lower central portion of the wall 22 opposite the window I26, a curved upper shield I29 being provided to obstruct upward rays of light which might otherwise annoy the operator when the cover I3 isopen.

The pilot lamp I2'I is preferably of the type which hasa clear glass bulb, so that the machine operator may readily judge the condition of the record disk Dby the apparent clarity of the lamp filament as seen through said disk. The filament will, of course, appear blurred and distorted when grooves are present in the disk D, due to the difi'using effect of said grooves, while the lamp filament may be clearly seen after the grooves have been obliterated from the disk. The customary indicia I2'Ia (Figs. 2 and 3) which are applied to the end of the lamp bulb by the manufacturer in order to show its rating, will also be seen with varying degrees of definition depending J upon the condition of the record grooves.

It will be understood, however, that th automatic features of the disk reprocessing machine will render unnecessary any constant or repeated inspection of the disks being reprocessed.

Electrical circuits (Fig. 11)

The machine is provided with a connecting cord I30 which enters the rear compartment II through an aperture in the back plate 25, and which has an outer two-prong plug I3! for connection to a suitable source of electric current. The connecting cord I30 has a pair of conductors I32, I33, the former being connected to a. main switch 134 and the latter being connected to a return conductor I35 which serves as the equivalent of a common ground for the various machine circuits.

In practice, provision may be made of a connecting block I36 (Figs. 1 and 4) to which the cord I 30 is connected and which will serve as a convenient means for connecting other portions of the machine circuits.

The main switch I35 is operatively connected 1 to the switch knob It by means of a shaft I3'I (Fig. 4) which is rotatably supported in the front wall 21 and the transverse wall 22, and is provided with a mechanically connected but electrically separate momentary contact switch I38 (Fig. 11) to be further described hereinafter.

The heaters 39, 40, the thermostat and the main switch I3d are all series-connected so as to provide a heater circuit connected to the conductors I32, I33, this being accomplished by means of a conductor I39 connecting the main switch I34 to the thermostat 5i, a conductor I40 connecting the thermostat 55 to the heater 40, conductors MI and M2 having an interposed high-temperature fuse M3 connecting the heater 40 to the heater 33, and a conductor I44 connecting the heater 39 to the return wire I35.

Thus, it will be seen that, when the main switch I34 is closed, the heaters 39, 40 will be energized until such time as the heating chamber I5 reaches a predetermined temperature, at which time the thermostatic switch 5| will open. The fuse I63 is for the purpose of protecting the machine against abnormally high temperatures, and is so constructed as to break the heater circuit in the event of an accidental and excessive rise in temperature.

A convenient means for use in testing the heaters 39, 43 is provided in the form of a test lamp I45 which is located in a circuit which includes a conductor I45 connected to the conductor MI, and a conductor I41 connected to the return conductor I35. The test lamp I45 may be supported in a socket I48, attached to the top member 55 of the inner cover frame (Fig. 1). When the main switch I34 and th thermostatic switch 5I are closed, a proper operating condition of the heaters 39, will be indicated by a dim glow in the test lamp I45. A defect in the heaters 39, 40 will be indicated either by failure of the testlamp I to burn at all, or by a bright illumination thereof. The test lamp I45 may also be used in testing the thermostatic switch 5I, inasmuch as the operation of said test lamp depends upon the operation of said switch 5|.

indicate the condition of the main switch I34 when the plug I3Iis connected to a source of current.

lhe motor 84 is provided with a pair of lead wires I5 I, I52 which are adapted to be connected into a motor circuit of the machine by means of a separable plug and socket device I53 (Figs. 4 and 11). The plug and socket device I53 has a conductor I54 for connecting the motor wire. I5I to the return conductor I35, and a conductor I55 for connecting th motor wire I52 to the contact of the motor switch I04, whereby operation of the motor 84 will be subject to operation of said switch I04.

The other contact I06 of the motor switch Ill l is not connected directly to the main switch I34, however, but is connected by means of. a wire I551; to one arm I56 of a two-armrelay I51 which is provided for the purpose of preventing operation of the machine during a warmingup period which occurs just after the main switch I34 has been turned on, and in which the heaters 39, 40 will be too cool for effective use.

The relay arm I56 is normally in engagement with a relay contact I58 which is connected to the main switch conductor I39 by means of a conductor may be effective to energize the motor 84. However, when the operator turns on the main switch I35, the momentary contact switch arm I38 will be caused to brush across a contact I50 immediately after said main switch has established contact between the conductors I32 and I39.

This action will momentarily provide a circuit through an actuating coil IGI of the relay I5'I, said circuit including a conductor I62 between the load side of the thermostatic switch 5I and the contact I 60, and a conductor I53 between the momentary contact switch arm I38 and one side of the relay coil NH. The other side of the relay coil I61 is connected in series with a resistor I5 3 to the ground conductor I35 by means of wires I55, I56, in order to permit a limited current to flow through said relay coil IBI when the 'machine is being operated upon direct current.

However, when the machine is to be operated upon alternating current, the resistor I54 will be short-circuited by means of a jumper IBI which is adapted to connect the conductor I54 to the wire I55 through a conductor I68. The jumper IE! may conveniently be included in the plug and socket device I53. Thus, it will be understood that the machine may be readily converted for A. C. or D. C. operation by the provision of interchangeable A. C. and D. C. motors 84, the jumper IIi'I being included only in a connecting plug attached to the A. C. motor.

Returning now to the relay I51, it will be seen I59, whereby the motor switch I04 that the operation of the momentary contact. switch I38 will energize the relay coil I 6I so as to separate the relay arm I56 from the contact I58 and thus prevent the operation of the motor 84. Since this action is only momentary, however, provision is made of a relay holding circuit which will be effective when the heaters 39, 40 are below their proper operating temperature and the thermostatic switch is closed, and which comprises a second relay arm I69 adapted to engage a relay contact I10 when the coil IBI is energized. The arm I69 is connected to one side of said relay coil through the conductor I63, while said contact I10 is connected to the load side of the thermostatic switch I through the conductor I62. Thus, once the relay I51 has been actuated by the momentary contact switch I38, the second relay arm I69 will establish a circuit through the relay coil I6I and the thermostatic switch 5|, said circuit being maintained so as to hold the motor circuit open as long as said thermostatic switch remains closed.

When the heaters 39, 40 have attained a temperature which is suiiicient to reprocess a record disk efficiently, the thermostatic switch 5I will open, thus breaking the circuit through the relay coil I6I and permitting the relay arm I56 to close against the contact I58 so as to allow a machine cycle to be initiated when the motor switch I04 is operated.

The thermostatic switch 5| will, of course, close at intervals in order to maintain a proper operating temperature in the heaters 39, 40. Such closing action will be ineffective to disable the motor circuit, however, inasmuch as the relay holding circuit through the second relay arm I69 can be established only by operation of the momentary contact switch I38.

In order to improve the operation of the thermostatic switch 5|, provision is preferably made of a capacitor I1I which is connected across said switch by means of wires I12, I13 attached to the conductors I39, I62, respectively.

Operation In preparing the machine for use, the plug I3I will first be connected to a suitable source of power and the knob I6 will be turned so as to close the main switch I34. Inasmuch as the heaters 39, 40 will be cool at this time, the thermostatic switch 5| will be in a closed condition so that the heaters 39, 40 will be energized and the relay I51 will hold the circuit of the motor 84 open, said circuit having first been opened by the action of the momentary contact switch I38 attendant upon operation of the main switch I34.

During the preliminary warming-up period of the heaters 39, 40 operation of the motor switch I04 will be ineffective to start operation of the motor 84. As soon as the heaters 39, 40 have reached their proper operating temperature, however, the thermostatic switch 5| will open and thus deenergize the relay coil I6I.

If this occurs when the machine is in condition to initiate a machine cycle (in which condition the cover I3 is open, the motor switch I04 is in a vertical position, and the shut-off cam holds the contacts I06, I01 disconnected by means of the spring I I 9 and the operating button I05) the operator may start the motor 84 by pressing the button I1. However, if the relay coil I6I should become deenergized when the machine is in a condition corresponding to an intermediate point in the machine cycle (as in Fig. 8, for example) 12 the contacts I 06, I01 would already be connected, thus causing the motor 84 to start automatically and complete the machine cycle. At the end of the cycle, the cover I3 will, of course, be in open position.

Thus, a proper operating temperature of the heaters 39, 40 may be indicated to the user by the starting of the operation of the motor 84.

A used record disc D to be reprocessed will then be placed upon the spindle I4 and the knob 8I applied to said spindle so as to clamp the disk D in place thereon. The operator will then initiate a machine reprocessing cycle by pressing the starting button I1 so as to tilt the motor switch I04 into the position shown in Fig. 7 thus starting the motor 84. The latter will, of course, rotate the spindle I4 and the disk D thereon at a rapid rate, while simultaneously rotating the slow speed shaft 9I in a counter-clockwise direction as viewed in Figs. 6, 7, and 8.

The starting button I1 will be held inwardly manually for a short time in order to permit the projecting cam screw II1 to swing out of the path of the leaf spring H9 on the motor switch I 04 whereupon the button I1 may be released so as to permit the coil spring II3 to return the motor switch I04 to a vertical position. The

contacts I06, I01 will remain connected, however,

until the end of the machine cycle, when the projecting cam screw I I1 will have made a complete revolution and again engaged the leaf spring II9 so as to disconnect the motor switch contacts I06, I01.

The machine cover I3 will close at the beginning of the machine cycle, at which time the cam follower 96 will enter upon the flat edge portion 98 of the cover lifting cam 92. The rotating disk D will be subjected to the heat radiated by the heaters 39, 40 as long as the cover I3 is closed. The internal strains in the material of the disk D will be relieved during this period, at the end of which the cam follower 96 will ride outwardly upon the circular cam portion 91, thus opening and holding the cover I3 so that the disk D will no longer be under the influence of the heaters 39, 40.

The circular edge portion 91 of the cam 92 will provide a cooling period during which the rotation of the disk D will be continued, at the end of which period termination of the machine cycle will occur as described above. It will be understood that the cooling period will be of sufiicient length to permit the disk D to recover its original stiffness, after which said disk may be removed and replaced by another disk to be reprocessed.

After the machine has been in operation for a short time, the parts surrounding the forward compartment I2 and the heaters 39, 40 will have become heated to such a point that it may be desirable to adjust the temperature control knob I8 to a slightly lower setting in order to maintain the proper operating temperature in the heating chamber I5. An excessive temperature in the heating chamber I5 may be indicated, for example, by a slight warping or cupping of the disks D, and may also be indicated by a toorapid disappearance of the record grooves as observed through the window I26.

In the event that prolonged use of the machine should cause the clamping knob 8| to become too hot for comfortable handling, the operator may lay said knob aside temporarily so as to permit it to cool while using the spare knob 8Ia for clamping the disks upon the spindle I4.

When the operation of the machine is to be discontinued, the operator will merely turn the knob It so as to disconnect the main switch 134. The pilot lamp I21 will, of course, serve as a warning against leaving the machine turned on.

Inasmuch as the counter i2i) will register the number of cycles performed by the machine, said counter will provide an accurate indication of the number of disks reprocessed.

Although it has been found in practice that the machine requires very little maintenance service, access to the mechanism in the rear compartment H may readily be had merely by releasing the lock 66 and removing the screws 64, 65, so as to permit the cover shield 51 to be removed from the inner cover frame 36.

In the event that the heaters 39, 411 are suspected of being out of order, a test lamp may be inserted in the socket 148 While the heater conductors i 19 and Mt are energized. As hereinbefore described, a proper operating condition of the heaters 39, it will be indicated by a dim glow in the test lamp [45, while any other condition of the lamp will indicate that one or both of said heaters is out of order.

While there has been disclosed in this specification one form in which the invention may be embodied, it is to be understood that this form is shown for the purpose of illustration only,

and that the invention is not to be limited to the specific disclosure, but may be modified and embodied in various other forms without departin from its spirit. In short, the invention inably mounted holding means for engaging the central portion of a record disk and supporting the disk for rotation about its normal axis, a heating chamber for heating said record disk to erase said grooves therefrom, means mounting said heating chamber for movement into effective position wherein it embraces said disk, and into ineffective position wherein it is separated from the disk, drive means for rotating said holding means and the disk thereon to maintain the disk flat by centrifugal force while the disk is in a heated condition, and means comprising a thermostatic device for holding said drive means inoperative while the temperature of said heating chamber is below a predetermined value.

2. In a machine for restoring used thermoplastic phonograph record disks in which grooves have been impressed; the combination of a rotata'bly mounted holding means for engaging the central portion of the record disk and supporting the disk in a vertical plane for rotation about its normal axis, a heating chamber for heating said record disk to erase said grooves therefrom, means mounting said heating chamber for movement into an efiective positionwherein it embraces said disk, and into ineffective position wherein it is separated from the disk, electric motor drive means for rotating said holding means and the disk thereon to maintain the disk flat by centrifugal force while the disk is in a heated condition, an energizing circuit for said motor, a switch in said circuit, a slow speed shaft operatively connected to said drive means, mechanism comprising a first cam on said slow speed shaft for moving said heating chamber, and mechanism comprising a second cam on said slow speed shaft for operating said switch to control said drive means.

3. The invention as defined in claim 2 including manually-operable means for actuating said switch at the beginning of a machine cycle.

4. In a machine for restoring used thermoplastic phonograph record disks in which grooves have been impressed; the combination of a rotatably mounted holding means for engaging the central portion of a record disk and vertically supporting the disk for rotation about its normal axis, a heating chamber for heating said record disk to erase said grooves therefrom, vertically swingable means supporting said heating chamher for movement into an effective position wherein said chamber embraces a portion of said disk, and into an ineffective position wherein said chamber is separated from the disk, adjustable resilient means for partially counterbalancing the weight of said supporting means and the heating chamber thereon, and drive means for rotating said holding means and the disk thereon to maintain the disk flat by centrifugal force While the disk is in a heated condition.

5. In a machine for restoring used thermoplastic phonograph record disks in which sound tracks have been impressed; the combination of a body portion having a shallow forward well, a rotatably mounted holding means for engaging the central portion of a record disk and supporting the disk for rotation in a vertical plane about its normal axis with the lower portion of the disk disposed in said well, a vertically swingable cover for said body portion, said cover being mounted upon a horizontal shaft supported by said body portion, the forward portion of said cover having a heating chamber for enclosing the remainder of said disk and heating said record disk to erase said grooves therefrom when said cover is closed, said heating chamber being ineffective upon the disk when said cover is open, and drive means for rotating said holding means and the disk thereon to maintain the disk flat by centrifugal force while the disk is in a heated condition.

6. In a machine for restoring to their original fiat-surfaced condition used light transmitting thermoplastic phonograph record disks in which grooves have been impressed; the combination of a holding means, for engaging the central portion of a record disk and supporting said disk in a vertical plane, means comprising a heater for erasing the grooves in said disk, a lamp disposed behind said disk to permit the erasure of said grooves to be observed from the front of and through said disk, said lamp comprising a light transmitting bulb having indicia thereon, whereby the apparent distortion of the image of said indicia as viewed through said disk will be a sensitive indication of the degree of restoration of the disk to its original fiat-surfaced condition.

NILS T. ALMQUIST. ANTHONY C. DE NAPOLI, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,351,865 Nicol Sept. 7, 1920 2,265,032 Feyrer Dec. 2, 1941 2,340,161 Van Deventer Jan. 25, 1944 2,388,127 Downing Oct. 30, 1945 

